In recent years, there have been proposed and developed various backlash adjusters in which a pressing force is applied by deflection (elastic deformation) of an elastic body in a manner so as to press a worm against a worm wheel. One such backlash-adjuster equipped power steering device has been disclosed in Japanese Unexamined Patent Application Publication No. 2004-345444 (hereinafter is referred to as “JP2004-345444”). In the backlash adjusting technologies, as disclosed in JP2004-345444, owing to a displacement of the worm toward the worm wheel, arising from wear, the amount of deflection of the elastic body decreases, thus causing a decrease of the pressing force. Hence, such a backlash adjuster has the difficulty of producing and/or holding a stable pushing force. A backlash adjuster, capable of producing and/or holding a more stable pushing force, would be desirable.